ia*; T

.atz

recognized experts in the subject areawill summarize thebest available evidence relating to the topic while including

of those practices out of date. We discuss our approach to

usually caused by another source that needs to be

represents a continuum, rather than a dichotomous state.

failure may have time for pharmacologic intervention. We

emergency physicians have found that by cautiously

CARDIOLOGY/EXPERT CLINICAL MANAGEMENTaddressed. For these patients, it may be helpful to slow thepulse rate slightly to reduce myocardial demand, but recallthat many of them will require a relatively fast pulse rate tocompensate for their decreased stroke volume (otherwise,their cardiac output will decrease).

slowing the pulse rate with intravenous diltiazem, theblood pressure actually increases, presumably becauseof increased ventricular lling time. If this option isselected, doses should be administered in small amounts,followed by assessment of the response.long history of atrial brillation, with an abnormally highpulse rate because of their acute illness. These patients willlikely not convert with the immediate cardioversion that isrecommended in atrial brillation guidelines3,5,7 becausethe atrial brillation is long-standing. Their hypotension is

DiltiazemIn all guidelines, it is recommended that nondihydropyridine

calcium-channel blockers (eg, diltiazem) be avoided in thesetting of hypotension or heart failure, although the qualityof evidence for the recommendation is poor.2,5,7 Manythe ED patient with atrial brillation (or atrial utter, forwhich the recommendations are the same) according to themost recent guidelines1-9 and our expertise in the area.10-17

THE UNSTABLE PATIENTFirst, it is important to carefully consider why the

patient is unstable and whether the atrial brillation is thecause. Many patients are hypotensive as a result of sepsis,gastrointestinal hemorrhage, or other causes, and have apractical recommendations where the evidence isincomplete or conicting.

INTRODUCTIONAlthough most emergency physicians will have an

established routine for managing the emergencydepartment (ED) patient with atrial brillation, in the last4 years 9 new updates and guidelines for the managementof these patients have been published by European,Canadian, and US professional groups,1-8 rendering manyManaging AtrClare L. Atzema, MD, MSc

*Corresponding Author. E-mail: clare

0196-0644/$-see front matterCopyright 2015 by the American College of Emergency Physicians.http://dx.doi.org/10.1016/j.annemergmed.2014.12.010

[Ann Emerg Med. 2015;-:1-8.]Editors Note: The Expert Clinical Management seriesconsists of shorter, practical review articles focused on theoptimal approach to a specic sign, symptom, disease,procedure, technology, or other emergency departmentchallenge. These articlestypically solicited fromVolume -, no. - : - 2015guideline recommendations and approaches we routinely use.

AmiodaroneAmiodarone is used for rate control in this setting, not

for cardioversion (which usually takes 4 to 6 hours withintravenous amiodarone).5,7 However, anticoagulation(with heparin) is advisable, given that cardioversion tonormal sinus rhythm may occur with this drug.

DigoxinAnother guideline-endorsed option is intravenous

digoxin. Although slow in onset, anecdotally it oftenimproves the blood pressure within 30 minutes.18outline an approach to one of the most challenging unstableatrial brillation patients, the hypotensive, conscious patientwith atrial brillation of unknown duration (Figure 1).Challenging because sedation may worsen the hypotension,but cardioversion without sedation should be avoided. Thereare relatively few data to support any of the outlinedapproaches (or one over another); they represent bothAlthough a patient who is losing consciousness is clearlyunstable (and requires immediate cardioversion despite therisk of stroke if the duration of atrial brillation is >48hours), the tachypneic patient with early signs of heartl Fibrillationyler W. Barrett, MD MSCI

ema@ices.on.ca, Twitter: @Atzema.

Second, we contend that the denition of stabilityAnnals of Emergency Medicine 1

Figure 1. Management options for the hypotensive, conscious patient, which may be attempted to avoid immediate cardioversion. We recommend selecting only 1 ofthe 3 options; if not effective (pulse rate decreased and blood pressure increased or maintained), obtain expert consultation. If vital signs or level of consciousnessworsens, proceed to immediate cardioversion.

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Atzema & Barrett Managing Atrial FibrillationTHE STABLE PATIENTMost ED atrial brillation patients will be alert, with a

well-perfusing blood pressure. Approximately 20% ofthese patients will experience chest pain with the fastpulse,19 but in the majority this is demand-relatedIn the clearly unstable patient, immediate electricalcardioversion is required (Figure 1). If possible,administer heparin rst.1 Given the time of onset forsubcutaneous heparin, we use intravenous heparin in thissituation.

Table 1. Common rate-control options in the ED: generally startingsame class (administered once the pulse rate is controlled [

Managing Atrial Fibrillation Atzema & Barrettb-blockers with calcium-channel blockers, we recommendusing one or the other, not both.

The evidence for b-blockers versus calcium-channelblockers is weak: several studies found no difference inoutcomes,26 other than a possible worsening of exercisetolerance with b-blockers.27 Another found that inpatients older than 65 years, calcium-channel blockerswere associated with higher 90-day mortality in EDpatients with atrial brillation12; however, indication biasis a possibility in that retrospective study. In our practice,we tend to use b-blockers for patients with coronary arterydisease6 (given that several hypertension guidelinesrecommend b-blockers for those with a history of anginaor myocardial infarction)28,29 and diltiazem for otherpatients.

The goal of rate control varies by guidelines: less than110 beats/min for European2 and US guidelines (but thelatter stipulates that patients have a normal left ventricularejection fraction),5 and less than 100 beats/min forCanadian guidelines.30 All are based on the Rate ControlEfcacy in Permanent Atrial Fibrillation: a Comparisonbetween Lenient versus Strict Rate Control II (RACE II)trial, which found no difference in patient outcomes withtight control (resting pulse rate

guuro

Atzema & Barrett Managing Atrial Fibrillationdetermine oral anticoagulation eligibility. The American

Figure 3. Recommendations for who should receive oral anticoawith permission from Oxford University Press on behalf of the ECanadian Cardiovascular Society.Heart Association recommends oral anticoagulation forCHA2DS2-VASc score greater than or equal to 2, and thechoice of oral anticoagulation or aspirin or nothing for a scoreof 1. In comparison, the European Society of Cardiologyrecommends oral anticoagulation for CHA2DS2-VASc scoregreater than or equal to only 1.3,5 There remain fewindications for aspirin therapy (Figure 3). To assess bleedingrisk, all guidelines endorse HAS-BLED (Figure 4), in which ascore greater than or equal to 3 indicates high risk ofbleeding.41

*

Figure 4. HAS-BLED tool for assessing risk of bleeding (scoreof 3 indicating high risk of bleeding). *Hypertension denedas systolic pressure 160 mm Hg. Labile INR dened aswithin therapeutic range < 60% of the time. Drugs dened asantiplatelet drugs (eg aspirin, clopidogrel), alcohol 8 drinksper week.

Volume -, no. - : - 2015Our recent study found that discharged ED atrial

lation or aspirin across professional groups. Figures reproducedpean Cardiovascular Society and Elsevier, Inc on behalf of thebrillation patients who were eligible for oral anticoagulationwere much more likely to be receiving it a year later (75%) ifthey were provided with a prescription in the ED compared tothose for whom oral anticoagulation initiation was left to the

Table 2. Typical dose selection for oral anticoagulants initiated inthe ED for patients without evidence of renal failure (eg, creatinineclearance >60 mL/minute), with instructions to follow up with theprimary care provider.2,5,9

OralAnticoagulant Patient Initiating Dose/Prescription

Warfarin 70 kg 5 mg once daily35 days;obtain INR

60 kg orage 80 y

2.5 mg once daily35 days;obtain INR

Novel oral anticoagulantsDabigatran 70 kg 150 mg twice daily12 wk

60 kg orage 80 y

110 mg twice daily12 wkUS: 75 mg twice daily12 wk*

Rivaroxaban 70 kg 20 mg once daily12 wk60 kg orage 80 y

15 mg once daily12 wk

Apixaban 70 kg 5.0 mg twice daily12 wk60 kg orage 80 y

2.5 mg twice daily12 wk

*This is the Food and Drug Administration recommended dose, based on modelingstudies; however, it has not been prospectively validated. Other countries use 110 mgtwice a day as the lower dose.

Annals of Emergency Medicine 5

primary care provider (34%).42 The sample size was small; years: 64% of visits made by these patients resulted in

Managing Atrial Fibrillation Atzema & Barretthowever, a larger study with long-term outcomes is not likelyto be soon forthcoming. The study suggests that theemergency physician has an opportunity to decrease thepatients long-term risk of stroke. Given the overwhelmingevidence that oral anticoagulation prevents strokes,43 weinitiate eligible patients on oral anticoagulation in the ED(Table 2).

Whether a novel oral anticoagulant is preferable towarfarin depends on the guidelines consulted, and,more importantly, the patients ability to stay withintherapeutic range (International Normalized Ratio [INR]2-3) while receiving warfarin. If patients can stay inrange most of the time (>60-65% of the time), theirprotection against stroke is likely better than with thenovel oral anticoagulants.44-46 However, many patientscannot achieve this; therefore, novel oral anticoagulantsmay be better for most. Currently, dabigatran,rivaroxaban, and apixaban are approved for use innonvalvular atrial brillation by the Food and DrugAdministration, Health Canada, and the EuropeanMedicines Agency.

Dabigatran is cleared exclusively through the kidneys.Although the drug can be used with certain levels of renalfailure, as emergency physicians (who do not followpatients), we would not routinely offer dabigatran, or anynovel oral anticoagulants, to anyone with any suggestion ofrenal failure. In the Randomized Evaluation of Long-TermAnticoagulation Therapy (RE-LY) trial, the RivaroxabanOnce daily oral direct factor Xa inhibition Comparedwith vitamin K antagonism for prevention of strokeand Embolism Trial in AF (ROCKET-AF) trial, andthe Apixaban for Reduction in Stroke and OtherThromboembolic Events in Atrial Fibrillation(ARISTOTLE) trial, dabigatran, rivaroxaban, and apixabanhad a lower rate of life-threatening bleeding thanwarfarin.44-47 Reversal agents are not yet available for noveloral anticoagulation (compared with 4-factor prothrombincomplex concentrate for warfarin) but are likely to come tomarket in the next 2 years. Patients with mechanical heartvalves or hemodynamically signicant mitral stenosisshould be treated only with warfarin (they were excludedfrom the novel oral anticoagulant trials).44-46

Disposition From the EDIn recent collaborative work, we found that 69% of ED

visits with a primary diagnosis of atrial brillation resultedin hospitalization in the United States compared with37% in Canadas most populous province.48 The largestintercountry variation was for patients younger than 656 Annals of Emergency Medicinehospitalization in the United States versus 25% in theCanadian cohort. Several Canadian studies have suggestedthat discharge home is safe.11,33 Presumably the youngerUS patients are being admitted for further testing; however,this can be performed on an outpatient basis. Werecommend that hospitalization be reserved for patientswith the following: another ED diagnosis (eg, pneumonia),presence of acute coronary syndrome or heart failure, orfailure of rate control (unable to achieve

5. January CT, Wann LS, Alpert JS, et al. 2014 AHA/ACC/HRS guideline 23. Wyse DG, Waldo AL, DiMarco JP, et al. A comparison of rate control and

Atzema & Barrett Managing Atrial Fibrillationfor the management of patients with atrial brillation: a report of theAmerican College of Cardiology/American Heart Association TaskForce on Practice Guidelines and the Heart Rhythm Society.Circulation. 2014;64:e1-e76.

6. Skanes AC, Healey JS, Cairns JA, et al. Focused 2012 update of theCanadian Cardiovascular Society atrial brillation guidelines:recommendations for stroke prevention and rate/rhythm control. Can JCardiol. 2012;28:125-136.

7. Stiell IG, Macle L. Canadian Cardiovascular Society atrial brillationguidelines 2010: management of recent-onset atrial brillationand utter in the emergency department. Can J Cardiol. 2011;27:38-46.

8. Wann LS, Curtis AB, Ellenbogen KA, et al. 2011 ACCF/AHA/HRSfocused update on the management of patients with atrial brillation(update on Dabigatran): a report of the American College of CardiologyFoundation/American Heart Association Task Force on practiceguidelines. Circulation. 2011;123:1144-1150.

9. Verma A, Cairns JA, Mitchell LB, et al. 2014 Focused update of theCanadian Cardiovascular Society guidelines for the management ofatrial brillation. Can J Cardiol. 2014;30:1114-1130.

10. Atzema CL, Lam K, Young C, et al. Patients with atrial brillation and analternative primary diagnosis in the emergency department: adescription of their characteristics and outcomes. Acad Emerg Med.2013;20:193-199.

11. Atzema CL, Austin PC, Miller E, et al. A population-based description ofatrial brillation in the emergency department, 2002 to 2010. AnnEmerg Med. 2013;62:570-577.

12. Atzema CL, Austin PC, Chong AS, et al. Factors associated with 90-daydeath after emergency department discharge for atrial brillation. AnnEmerg Med. 2013;61:539-548.

13. Atzema CL, Dorian P, Ivers NM, et al. Evaluating early repeat emergencydepartment use in patients with atrial brillation: a population-basedanalysis. Am Heart J. 2013;165:939-948.

14. Barrett TW, Martin AR, Storrow AB, et al. A clinical prediction model toestimate risk for 30-day adverse events in emergency departmentpatients with symptomatic atrial brillation. Ann Emerg Med. 2011;57:1-12.

15. Barrett TW, Self WH, Jenkins CA, et al. Predictors of regional variationsin hospitalizations following emergency department visits for atrialbrillation. Am J Cardiol. 2013;112:1410-1416.

16. Barrett TW, Jenkins CA, Self WH. Validation of the Risk Estimator DecisionAid for Atrial Fibrillation (RED-AF) for predicting 30-day adverse events inemergency department patients with atrial brillation. Ann Emerg Med. Inpress.

17. Barrett TW, Abraham RL, Self WH. Usefulness of a low CHADS2 orCHA2DS2-VASc score to predict normal diagnostic testing in emergencydepartment patients with an acute exacerbation of previously diagnosedatrial brillation. Am J Cardiol. 2014;113:1668-1673.

18. National Library of Medicine. Dailymed. Lanoxindigoxin. Available at:https://dailymed.nlm.nih.gov/dailymed/archives/fdaDrugInfo.cfm?archiveid13577. Accessed November 25, 2014.

19. Stiell IG, Clement CM, Brison RJ, et al. Variation in management ofrecent-onset atrial brillation and utter among academic hospitalemergency departments. Ann Emerg Med. 2011;57:13-21.

20. Zimetbaum PJ, Josephson ME, McDonald MJ, et al. Incidence andpredictors of myocardial infarction among patients with atrial brillation.J Am Coll Cardiol. 2000;36:1223-1227.

21. Brown AM, Sease KL, Robey JL, et al. The risk for acute coronarysyndrome associated with atrial brillation among ED patientswith chest pain syndromes. Am J Emerg Med. 2007;25:523-528.

22. Van Gelder IC, Hagens VE, Bosker HA, et al. A comparison of ratecontrol and rhythm control in patients with recurrent persistent atrialbrillation. N Engl J Med. 2002;347:1834-1840.Volume -, no. - : - 2015rhythm control in patients with atrial brillation. N Engl J Med.2002;347:1825-1833.

24. David D, Segni ED, Klein HO, et al. Inefcacy of digitalis in the control ofheart rate in patients with chronic atrial brillation: benecial effect of anadded beta adrenergic blocking agent. Am J Cardiol. 1979;44:1378-1382.

25. Yancy CW, Jessup M, Bozkurt B, et al. 2013 ACCF/AHA guideline forthe management of heart failure: a report of the American College ofCardiology Foundation/American Heart Association Task Force onpractice guidelines. Circulation. 2013;128:e240-e327.

26. Scheuermeyer FX, Grafstein E, Stenstrom R, et al. Safety and efciencyof calcium channel blockers versus beta-blockers for rate control inpatients with atrial brillation and no acute underlying medical illness.Acad Emerg Med. 2013;20:222-230.

27. Ahmad K, Dorian P. Rate control in atrial brillation: looking beyond theaverage heart rate. Curr Opin Cardiol. 2006;21:88-93.

28. Dasgupta K, Quinn RR, Zarnke KB, et al. The 2014 CanadianHypertension Education Program recommendations for bloodpressure measurement, diagnosis, assessment of risk,prevention, and treatment of hypertension. Can J Cardiol.2014;30:485-501.

29. Mancia G, Fagard R, Narkiewicz K, et al. 2013 ESH/ESC guidelines forthe management of arterial hypertension: the Task Force for theManagement of Arterial Hypertension of the European Society ofHypertension (ESH) and of the European Society of Cardiology (ESC).J Hypertens. 2013;31:1281-1357.

30. Gillis AM, Verma A, Talajic M, et al. Canadian Cardiovascular Societyatrial brillation guidelines 2010: rate and rhythm management. Can JCardiol. 2011;27:47-59.

31. Van Gelder IC, Groenveld HF, Crijins HJ, et al. Lenient versus strict ratecontrol in patients with atrial brillation. N Engl J Med. 2010;362:1363-1373.

32. Michael JA, Stiell IG, Agarwal S, et al. Cardioversion of paroxysmalatrial brillation in the emergency department. Ann Emerg Med.1999;33:379-387.

33. Stiell IG, Clement CM, Perry JJ, et al. Association of the Ottawa AggressiveProtocol with rapid discharge of emergency department patients withrecent-onset atrial brillation or utter. CJEM. 2010;12:181-191.

34. Stiell IG, Clement CM, Symington C, et al. Emergency department useof intravenous procainamide for patients with acute atrial brillation orutter. Acad Emerg Med. 2007;14:1158-1164.

35. Blecher GE, Stiell IG, Rowe BH, et al. Use of rate control medicationbefore cardioversion of recent-onset atrial brillation or utter in theemergency department is associated with reduced success rates.CJEM. 2012;14:169-177.

36. Kirchhof P, Eckardt L, Loh P, et al. Anterior-posterior versus anterior-lateral electrode positions for external cardioversion of atrialbrillation: a randomised trial. Lancet. 2002;360:1275-1279.

37. Kirkland S, Stiell I, AlShawabkeh T, et al. The efcacy of pad placementfor electrical cardioversion of atrial brillation/utter: a systematicreview. Acad Emerg Med. 2014;21:717-726.

38. Lip GY, Nieuwlaat R, Pisters R, et al. Rening clinical risk straticationfor predicting stroke and thromboembolism in atrial brillation using anovel risk factor-based approach: the euro heart survey on atrialbrillation. Chest. 2010;137:263-272.

39. Airaksinen KE, Gronberg T, Nuotio I, et al. Thromboemboliccomplications after cardioversion of acute atrial brillation: theFinCV (Finnish CardioVersion) study. J Am Coll Cardiol.2013;62:1187-1192.

40. Nuotio I, Hartikainen JE, Gronberg T, et al. Time to cardioversion for acuteatrial brillation and thromboembolic complications. JAMA. 2014;312:647-649.

41. Pisters R, Lane DA, Nieuwlaat R, et al. A novel user-friendly score(HAS-BLED) to assess 1-year risk of major bleeding in patients withAnnals of Emergency Medicine 7

atrial brillation: the Euro Heart Survey. Chest. 2010;138:1093-1100.

42. Atzema CL, Chong AS, Austin PC, et al. The long-term use of oralanticoagulation among atrial brillation patients discharged from anemergency department with a warfarin prescription. 2014.

43. Marini C, De Santis F, Sacco S, et al. Contribution of atrial brillation toincidence and outcome of ischemic stroke: results from a population-based study. Stroke. 2005;36:1115-1119.

44. Connolly SJ, Ezekowitz MD, Yusuf S, et al. Dabigatran versuswarfarin in patients with atrial brillation. N Engl J Med. 2009;361:1139-1151.

45. Granger CB, Alexander JH, McMurray JJ, et al. Apixaban versus warfarinin patients with atrial brillation. N Engl J Med. 2011;365:981-992.

46. Patel MR, Mahaffey KW, Garg J, et al. Rivaroxaban versus warfarin innonvalvular atrial brillation. N Engl J Med. 2011;365:883-891.

47. Ruff CT, Giugliano RP, Braunwald E, et al. Comparison of the efcacyand safety of new oral anticoagulants with warfarin in patients withatrial brillation: a meta-analysis of randomised trials. Lancet.2014;383:955-962.

48. Barrett TW, Vermeulen MJ, Self WH, et al. A population-based studycomparing the emergency department management of atrial brillationbetween the United States and Ontario, Canada. JACC. 2015. (In press).

Managing Atrial Fibrillation Atzema & Barrett8 Annals of Emergency Medicine Volume -, no. - : - 2015

Managing Atrial FibrillationIntroductionThe Unstable PatientAmiodaroneDigoxinDiltiazem

The Stable PatientRate or Rhythm ControlApproach to Rate ControlApproach to Rhythm ControlOral AnticoagulationDisposition From the ED

References